A RetrievalMethod instance may be created by invoking one of the
newRetrievalMethod methods
of the KeyInfoFactory class, and passing it the URI
identifying the location of the KeyInfo, an optional type URI identifying
the type of KeyInfo, and an optional list of Transforms; for example:

dereference

Dereferences the KeyInfo information referenced by this
RetrievalMethod and applies the specified
Transforms.

Parameters:

context - an XMLCryptoContext that may contain
additional useful information for dereferencing the URI. The
context's baseURI and dereferencer
parameters (if specified) are used to resolve and dereference this
RetrievalMethod

Returns:

a Data object representing the raw contents of the
KeyInfo information referenced by this
RetrievalMethod. It is the caller's responsibility to
convert the returned data to an appropriate
KeyInfo object.